Iron deficiency (ID) is associated with cardiovascular events such as stroke in children and cardiovascular disease (CVD) and all-cause mortality in adulthood. However, it is unknown whether ID in infancy contributes to the development of CVD and metabolic syndrome (cardio-metabolic risk). Studies of developmental effects of early ID demonstrate long-term negative effects on cognitive functioning, behavior, and socio-emotional development. Such changes may affect health behaviors that increase cardio-metabolic risk. Early adversity (e.g., poverty, maltreatment) is linked to higher cardio-metabolic risk and might also operate through similar cognitive, behavioral, and socio-emotional pathways. As ID is more common in low SES and other disadvantaged circumstances, a yet untested hypothesis is that there is a dual burden of having both ID and early adverse experiences that negatively affects functioning and subsequently increases cardio-metabolic risk. The goal of this project is to understand pathways between early ID and adversity and adult cardio-metabolic risk in order to identify targets for prevention and intervention and to detect subgroups at highest risk for disruptions in functioning and cardio-metabolic health. This goal will be accomplished using data from a large longitudinal study (n > 1000) of the effects of ID from infancy to early adulthood (PIs: Betsy Lozoff and Sheila Gahagan). Information on early ID and adversity (SES, life stress, maternal depression, father absence), adolescent cognitive functioning, health behaviors, and mental health, and adult cardio-metabolic risk (BMI, fat mass, blood pressure, blood lipids, hormonal regulators of metabolism) will be utilized. The first aim will test whether there are indirect effects of early ID on adult cardio-metabolic risk through pathways related to adolescent cognitive functioning, health behaviors, and mental health. The second aim will examine whether early adversity affects cardio-metabolic risk through similar or different pathways. The third aim will examine whether the dual burden of ID and adversity further increases cardio-metabolic risk in adulthood through these adolescent pathways. These aims will be accomplished with a training plan emphasizing the neurobiological and behavioral effects of early ID (sponsor Lozoff), childhood influences on cardio-metabolic risk (co-sponsor Gahagan), early adversity (Lozoff and Gahagan), and advanced statistical methods. Completing this research and training will be the first step in the PI's career plan to conduct policy-relevant research on the impact of nutrition and adversity on mental and physical health throughout the lifespan.